• Journal of Welding and Joining
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• v.9 no.4
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• pp.60-68
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• 1991

The weld quality of end cap welds in Pressurized Heavy Water Reactor (PHWR) Fuel is extremely important for the fuel performance in the nuclear reactor. The quality of resistance upset welds is currently evaluated mainly by the metallographic examination although it reveals only two weld cross-sections in a circumference welds. This investigation was, firstly, carried out to determine whether the ultrasonic examination would be applied to detect weld defects in the end cap welds and, secondly, to measure the mechanical strength of upset butt welds as a function of phase shift percentage. The major results obtained in this study are as follows: 1. The weld current and amount of upset shrinkage linearly increased with increasing the phase shift percentage. 2. Above the phase shift 55%, the defects in the welds were completely eliminated with increasing the phase of sound weld was over the thickness of cladding tube. 3. The ultrasonic testing well detected such defects in the end cap welds as upset external crack, upset split, corner crack and irregular weld flash comparing with the results of metallography. 4. The micro-fissure in the corner of the end cap welds was reliably detected by ultrasonic testing. 5. The mechanical strength in the welds increased with increasing phase shift percentage but the fracture did't occur in the welds above 55%.

• Journal of Korean Public Health Nursing
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• v.25 no.2
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• pp.197-208
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• 2011

Background: This study investigated the hearing status in Korean adults according to data from the Korea National Health and Nutrition Examination Survey 2009. Methods: The data of 3,479 adults(${\geq}20$ years, 1,492 men, 1,987 women) collected by the Korean Center for Disease Control was analyzed using ${\chi}^2$-test and logistic regression. Results: Differences in hearing loss according to individual factors were evident by follows gender, region, education status, economic status, current smoking and recognition of stress. Differences in - hearing loss according to ear related factors were evident subjective hearing status, experience of tinnitus, prevalence of chronic otitis media, and tympanomembrane abnormality. Conclusion: Hearing-related disorders can cause many social problems. This study investigated a representative cross-section of Koreans to determine the hearing status. The study was limited in that the risk factors of hearing loss were not identified. It is also recommended that a program be developed that can help control the variables identified in this study along with follow-up studies to verify the model.

• Korean Journal of Health Education and Promotion
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• v.31 no.2
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• pp.1-14
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• 2014

Objectives: This study aimed to investigate factors influencing suicidal ideation among Korean adults. Methods: Cross-sectional data from the fifth Korea National Health and Nutritional Examination Survey conducted in 2012 were analyzed in this study. The subjects were categorized into three groups by subjects' age(defined as young adults(20-39), middle-aged adults(40-59), and the elderly(60 or more). Data were analyzed by frequency, Chi-square test and multiple logistic regression using SPSS 18.0. Results: The factors influencing suicidal ideation were different among three age groups. The influencing factors were (1) gender, marital status, household income, perceived stress and depression in the young adult group, (2) household income, perceived health status, perceived stress and depression in the middle-aged group, (3) gender, regular physical activity, smoking, perceived health status, perceived stress and depression in the elderly group. Conclusions: The health education considering the characteristics of each age group should be developed and applied to prevent adults' suicidal ideation because the factors influencing suicidal ideation were revealed differently between the age groups.

• Journal of Technologic Dentistry
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• v.34 no.3
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• pp.315-324
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• 2012

Purpose: The purpose of this study was to survey dental prosthesis and dental prosthesis needs of elderly for improving oral health status. Methods: The data collected from 'The fifth Korean national health and nutrition examination survey 2010' was analyzed in this study. Statistical analysis was done using the Statistical Package for Social Sciences version 19.0 for Windows. We determined frequencies and percentage, calculating means, and standard deviations, and determined statistical significance using cross-tabulation analysis, logistic regression analysis. Results: General characteristics showed differences in mandible fixed crown bridge needs associated with periodontal disease. General characteristics showed differences in maxillar partial and full denture with gender, age, education, perceived oral health. General characteristics showed differences in mandible partial and full denture with age, residence, education, perceived oral health. Conclusion: In order to improve oral health of the elderly, Dental prosthesis support policy and oral health policy are necessary.

• Korean Journal of Remote Sensing
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• v.21 no.5
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• pp.383-392
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• 2005

Vegetation classes, especially grass and tree classes, are often confused in classification when conventional spectral pattern recognition techniques are used to classify urban areas. This paper reports on a study to improve the classification results by using an automated process of considering height information in separating urban vegetation classes, specifically tree and grass, using three-band, high-spatial resolution, digital aerial imagery. Height information was derived photogrammetrically from stereo pair imagery using cross correlation image matching to estimate differential parallax for vegetation pixels. A threshold value of differential parallax was used to assess whether the original class was correct. The average increase in overall accuracy for three test stereo pairs was $7.8\%$, and detailed examination showed that pixels reclassified as grass improved the overall accuracy more than pixels reclassified as tree. Visual examination and statistical accuracy assessment of four test areas showed improvement in vegetation classification with the increase in accuracy ranging from $3.7\%\;to\;18.1\%$. Vegetation classification can, in fact, be improved by adding height information to the classification procedure.

• The Korean journal of internal medicine
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• v.33 no.6
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• pp.1150-1159
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• 2018

Background/Aims: The aim of this study was to assess the association between the number of existing permanent teeth and chronic kidney disease (CKD) in a representative sample of the elderly Korean population. Methods: A total of 2,519 subjects who participated in the Korean National Health and Nutrition Examination Survey were cross-sectionally examined. The number of existing permanent teeth was evaluated by clinical oral examination. CKD was defined based on definition and classification by Kidney Disease: Improving Global Outcomes (KDIGO) 2012 guidelines. Multivariable logistic regression analyses were performed controlling for age, gender, income, education, tooth-brushing frequency, periodontitis, state of dentition, smoking, alcohol consumption, hypertension, obesity, diabetes mellitus, and hypercholesterolemia. Subgroup analyses by age and gender were also performed. Results: The number of teeth was significantly associated with CKD after controlling for all potential confounders (adjusted odds ratio [AOR], 1.67; 95% confidence interval [CI], 1.04 to 2.70 for lower number of teeth; AOR, 1.59; 95% CI, 1.14 to 2.23 for moderate number of teeth). In the subgroup analyses, the association was highlighted in females aged 75 years over (AOR, 2.55; 95% CI, 1.05 to 6.20 for lower number of teeth; AOR, 1.95; 95% CI, 1.01 to 3.80 for moderate number of teeth). Conclusions: Our findings suggest that the number of existing permanent teeth may be associated with CKD among Korean elderly.

• Nutrition Research and Practice
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• v.16 no.2
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• pp.194-204
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• 2022

BACKGROUND/OBJECTIVES: Sugar-sweetened beverages (SSBs) are regarded as modifiable risk factors for mental health in several populations. Although the consumption of SSBs is steadily increasing in Korea, there is scant evidence regarding the impact of SSB consumption on depression and suicidal ideation. The aim of this study was to investigate the association of SSB consumption with depression and suicidal ideation among adults in Korea. SUBJECTS/METHODS: We used the data for 5,465 participants (2,170 men and 3,295 women) aged ≥ 20 years from the 2014 and 2016 Korea National Health and Nutrition Examination Survey. The subjects were divided into four groups according to SSB consumption using a food frequency questionnaire. Logistic regression analyses were conducted to examine the association of SSB consumption with depression and suicidal ideation, adjusting for sociodemographic, health behavior, and dietary variables. RESULTS: Participants consuming ≥ 1 SSB/day had a significantly higher risk of depression (odds ratio [OR], 1.54; 95% confidence interval [CI], 1.08-2.18; P < 0.001) and suicidal ideation (OR, 2.20; 95% CI, 1.13-4.28; P < 0.001) compared with those in the non-SSB group after adjusting for potential confounding factors. CONCLUSIONS: Our results suggest that SSB consumption is positively associated with depression and suicidal ideation in Korean adults.

• Nutrition Research and Practice
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• v.16 no.1
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• pp.94-105
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• 2022

BACKGROUND/OBJECTIVES: The purpose of this study was to investigate the association between socioeconomic status and chewing discomfort and identify the role of food insecurity in the association's causal pathway in a representative sample of Korean elders. MATERIALS/METHODS: We conducted cross-sectional analyses of the Korea National Health and Nutrition Examination Survey (2013-2015) data for elders aged ≥ 65 years. Socioeconomic status indicators used included household income and education level. Chewing discomfort was assessed according to the self-reported presence of chewing problems. Food security was surveyed using a questionnaire based on the US Household Food Security Survey Module. RESULTS: The odds ratios of chewing discomfort in the 1st and 2nd income quartiles were 1.55 (95% confidence interval [CI], 1.15-2.10) and 1.40 (95% CI, 1.03-1.90), respectively, compared to participants in the highest income quartile. Participants with the lowest education level were 1.89 (95% CI, 1.30-2.75) times more likely to have chewing discomfort than those without chewing discomfort. After including food security in the final model, the logistic coefficients were attenuated in the income and education quartiles. CONCLUSIONS: Low socioeconomic status was associated with chewing discomfort. In addition, the results confirm that food insecurity can mediate the association between socioeconomic inequalities and chewing discomfort among the elderly.

• Journal of Korean Academy of Dental Administration
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• v.11 no.1
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• pp.1-7
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• 2023

The purpose of this study was to identify chronic diseases and oral health care behaviors in 65-year-old individuals and to determine the factors that influence masticatory mobility. The raw data from the 8th National Health and Nutrition Examination Survey in 2020 were utilized to analyze factors associated with chewing discomfort in 1,278 elderly Koreans. Using IBM SPSS Statistics 27.0, we conducted complex sample cross-analysis to examine the difference in chewing discomfort based on general characteristics, chronic diseases, and oral health care behaviors. Additionally, we performed complex sample multiple logistic regression analysis to identify the factors associated with chewing discomfort. As a factor influencing chewing discomfort, unmet dental care was 3.33 times higher (p<0.001), and subjective oral health was 0.18 times more likely to be moderate (p<0.001) and 0.48 times more likely to be good (p<0.001) lower. In the case of arthritis, the level of chewing discomfort was high (OR=1.08, p=0.694), but there was no significant difference. As a result of the aforementioned factors, it is believed that there is a need for policies and systems to provide dental care to the elderly before their oral health deteriorates. Additionally, tailored oral health promotion programs should be implemented.

• Journal of Korean Medical classics
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• v.26 no.4
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• pp.397-416
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• 2013

Objective : The recently reported Wuqian edition(吳遷本) Jinguiyaolue(金匱要略) is known to be written in small letters unlike other large lettered versions of the book. The Wuqian edition(吳遷本) takes after the name of Wuqian who copied an ancient version that was found at the time(Ming dyanasty, 1395). It is known to differ in organization and contents to other versions. In this study, I would like to examine how the small-lettered version of the Jinguiyaolue had been created, through a thorough examination of the Wuqian edition, and evaluate its value as a new version of the Jinguiyaolue. Method : First, the systems of both large-lettered and small-lettered versions of the "Jinguiyaolue" were briefly examined, followed by comparison from chapter 1 to 22, of organization, contents, and formulas between the oldest version of the large-lettered versions, the Deng-zhen edition, and the newly discovered Wuqian edition of which examples of each item are listed. The original source was identified for parts that were different. Result & Conclusion : 1. The Deng-zhen edition and Wuqian edition show vast differences in the organization, table of contents, name of chapter, location of each verse or line, existence of certain verses or lines, name of formula, quantity of medicinal ingredients, processing methods and other aspects. 2. The small-lettered edition was published based on the large-lettered edition of the Jinguiyaolue published by the Jiaozheng-yishuju(校正醫書局) after a general cross-examination process followed by selection, modification and supplementation of the large-lettered edition. Reference texts used in cross-examination were Qianjinyaofang(千金要方), Waitaimiyao(外臺秘要), Maijing(脈經), and Shanghanlun(傷寒論). 3. Considering Wuqian's own annotations and preface, it is clear that he wanted to create the best version of the "Jinguiyaolue". Wuqian himself seems to have had professional knowledge of bibliography and medicine.